Depression can come in many forms, and psychologists use a number of different terms to describe different types of depression. This information will help the average person better understand what each of these terms means. Some of these conditions will be further discussed in sections that follow.
Officially recognized forms of depression
Major depressive disorder
A major depressive episode is the standard diagnostic category used for depression. It is a depressive mood that lasts for at least 2 weeks. It may come on suddenly or gradually.
Persistent depressive disorder or dysthymic depression
Formerly called neurotic depression, the term dysthymia was coined in the 1980s to describe a less severe but more persistent depression that lasts for a year or more. It’s estimated to affect 1.5% of American adults over their lifetime. The average age of onset is 31, and it may occur alongside other depressive disorders. (Fieve, 2006, p.51)
Bipolar disorder
A depressive disorder in which a person alternates between manic highs and depressive lows. Often occurs alongside other mental health problems.
Postpartum depression
A type of depression that strikes new mothers (and also fathers) following the birth of a baby. While hormonal changes following pregnancy may play some role, it’s believed that things like adjusting to new roles and sleep deprivation caused by caring for a newborn are significant factors.
Postpartum depression is a subset of major depressive disorder.
Seasonal Affective Disorder (SAD)
A subtype of major depressive disorder, this is a depression that comes and subsides with the changing of the seasons, usually striking during the winter and subsiding during the summer. It is typically prevalent at higher altitudes and in colder climates, and is believed to be linked to sunlight and other environmental conditions that affect human physiology and alter mood.
Premenstrual dysphoric disorder (PDD)
A controversial diagnosis, PDD refers to depressive symptoms that emerge on a regular basis corresponding to a woman’s menstrual cycle.
Substance/medication-induced depressive disorder
A depressive mood that starts shortly after a person starts taking a substance or medication.
Depressive disorder due to another medical condition
A depressive mood induced by a particular medical condition (such as chemotherapy) as opposed to a mental health disorder.
Unspecified depressive disorder
Formerly known as depressive disorder not otherwise specified (NOS), this is a catch-all category that a clinician can use to diagnose someone who feels depressed but doesn’t actually meet the criteria for any of the other depressive disorders. It is a controversial category because by its very nature, it diagnoses people who don’t meet the criteria for having depression.
Other Terms Used To Describe Depression
Psychologists and professionals may also use the following terminology when describing depression:
Reactive depression
This is depression that occurs in response to a loss or serious disruption in life. It is a natural reaction to upsetting events and is only considered a problem if it does not subside within a reasonable amount of time. Also referred to as adjustment disorder.
Double depression
Used to refer to a mild depression that turns into a major depression, or when reactive depression morphs into major depression.
Secondary depression
Depression that occurs alongside another previously existing condition, whether physical (AIDS, cancer, Parkinson’s disease, etc.) or psychological (anxiety disorders, eating disorders, etc.). It is often believed to be a symptom of the other illness, and is considered secondary to it, hence the term.
Masked depression
A term that refers to depression mostly manifested through physical symptoms and somatic complaints. These patients often get labeled as hypochondriacs by their doctors, and may not recognize their physical symptoms as depression.
Chronic depression
Another term for a persistent depressive state.
Chronic treatment-resistant depression
This term is used to describe major depression that lasts more than a year and doesn’t respond to typical treatments, whether antidepressants or psychotherapy. Patients often turn to electroshock therapy as a last ditch effort.
Manic depression
Another term for bipolar disorder.
Episodic depression
A term used to describe depression that comes and goes, often a short-lasting depression.
Endogenous depression
A term used to describe depression where a cause isn’t easy to pinpoint.
Depression may take forms that don’t really fit within any of these categories. For example, one depression expert describes what he calls the weekend/holiday blues: a pattern in which people (usually those who are single and struggle with being alone), become depressed over the weekends or on holidays when their kids are spending time with the other parent. (Burns, 1980) We list these categories because it’s important to know what experts are talking about when they use these labels. But people are not labels, and no one person’s depression is precisely the same as another’s.